1. Field of the Invention
Aspects of the present invention relate in general to the field of communications network access security.
2. Background
The broadcast nature of wireless data transmission makes transmitted information susceptible to interception by third parties. Wireless networks, just like public networks, such as the Internet, must hence be considered insecure. As information transferred wirelessly between electronic devices is often of proprietary nature, there is a need to protect this information from eavesdropping.
Conventionally, one method of securing network access is by using encryption.
In a typical system using encryption, a sender encrypts the information using an encryption engine and an encryption key. The resulting information is rendered unintelligible to any party except to the recipient in possession of the decryption key. The recipient decrypts the received information using a decryption engine and the appropriate decryption key and thus translates the encrypted information into its original readable form.
Traditionally, the same key is used for both encryption and decryption. This is called “private key” or “symmetric” cryptography. Keys that are used for both encryption and decryption are referred to as “symmetric keys.” The shared key must remain secret since any party in possession of this key can decrypt information previously encrypted with the key. In order to establish a shared secret key, the key must be distributed among the communicating parties by means of a secure channel.
In public-key cryptography, the encryption key and the decryption key are distinct. The encryption key is public and can therefore be sent to the other party over an insecure communication channel. The decryption key is kept private and never revealed. To encrypt a message for a recipient, the sender uses the recipient's public encryption key. The encrypted message is then sent to the recipient over the insecure channel. The recipient uses its private decryption key to decrypt the received encrypted message.